A wireless local area network (WLAN) in infrastructure basic service set (BSS) mode has an access point (AP) for the BSS and one or more stations (STAs) associated with the AP. The AP typically has access or interface to a distribution system (DS) or another type of wired/wireless network that carries traffic in and out of the BSS. Traffic to STAs that originates from outside the BSS arrives through the AP and is delivered to the STAs. Traffic originating from STAs to destinations outside the BSS is sent to the AP to be delivered to the respective destinations. Traffic between STAs within the BSS (“peer-to-peer” traffic) may also be sent through the AP where the source STA sends traffic to the AP and the AP delivers the traffic to the destination STA. A WLAN in Independent BSS mode has no AP, and STAs communicate directly with each other.
WLAN systems which utilize beacon transmission procedures for discovery of the AP by the STA, use a periodic transmission of the beacon in the Basic Service Set (BSS) from the AP. The beacon supports various functions in the system by providing an AP Advertisement with the BSSID, Synchronization of the STAs in the BSS, capability information, BSS operation information, system parameters for medium access, transmit power limits, as well as many optional information elements. The frame format for typical beacons for WLAN BSSs may be >100 bytes long and in typical enterprise environment beacons are ˜230 bytes. The overhead of such a beacon may include a substantial amount of information. For example, a beacon of 100 bytes at the lowest transmission rate (100 Kbps) may require greater than 8 ms transmission time (i.e., at the lowest rate in order for all STAs to be able to decode it). For a beacon interval of 100 ms, there may be greater than 8% overhead. To support a 100 ms fast link setup time, beacon intervals must be significantly shorter than 100 ms, which would result in an overhead value significantly greater than the 8% overhead estimate.